“ULA is proud to deliver this critical satellite which will improve surveillance capabilities for our national decision makers,” said Laura Maginnis, ULA vice president of Government Satellite Launch. “I can’t think of a better way to kick off the new year.”

This mission was launched aboard an Atlas V Evolved Expendable Launch Vehicle (EELV) 401 configuration vehicle, which includes a 4-meter diameter large payload fairing (LPF). The Atlas V booster propulsion for this mission was powered by the RD AMROSS RD-180 engine, and the Centaur upper stage was powered by the Aerojet Rocketdyne RL10C engine.

Atlas V SBIRS GEO Flight 3 Launch Highlights

“The Atlas V 401 configuration has become the workhorse of the Atlas V fleet, delivering half of all Atlas V missions to date” said Maginnis. “ULA understands that even with the most reliable launch vehicles, our sustained mission success is only made possible with seamless integration between our customer and our world class ULA team.”

The Space Based Infrared System is designed to provide global, persistent, infrared surveillance capabilities to meet 21st century demands in four national security mission areas: missile warning, missile defense, technical intelligence and battlespace awareness.

This is ULA’s first launch of 11 planned launches in 2017 and the 116th successful launch since the company was formed in December 2006.

SBIRS GEO Flight 3 satellite

ULA's next East Coast launch is the Delta IV WGS-9 satellite for the U.S. Air Force. The launch is scheduled for March 8 from Space Launch Complex-37 at Cape Canaveral Air Force Station, Fla.

With more than a century of combined heritage, United Launch Alliance is the nation’s most experienced and reliable launch service provider. ULA has successfully delivered more than 115 satellites to orbit that aid meteorologists in tracking severe weather, unlock the mysteries of our solar system provide critical capabilities for troops in the field, and enable personal device-based GPS navigation and unlock the mysteries of our solar system.

New observations show that Ceres, the largest body in the asteroid belt, does not appear to have the carbon-rich surface composition that space- and ground-based telescopes previously indicated.

Using data primarily from NASA’s Stratospheric Observatory for Infrared Astronomy, SOFIA, a team of astronomers has detected the presence of substantial amounts of material on the surface of Ceres that appear to be fragments of other asteroids containing mostly rocky silicates. These observations are contrary to the currently accepted surface composition classification of Ceres as a carbon-rich body, suggesting that it is cloaked by material that partially disguises its real makeup.

“This study resolves a long-time question about whether asteroid surface material accurately reflects the intrinsic composition of the asteroid,” said Pierre Vernazza, research scientist in the Laboratoire d’Astrophysique de Marseille (LAM–CNRS/AMU). Our results show that by extending observations to the mid-infrared, the asteroid’s underlying composition remains identifiable despite contamination by as much as 20 percent of material from elsewhere,” said Vernazza.

Astronomers have classified the Ceres asteroid, as well as 75 percent of all asteroids, in composition class “C” based on their similar colors. The mid-infrared spectra from SOFIA show that Ceres differs substantially from neighboring C-type asteroids, challenging the conventional understanding of the relationship between Ceres and smaller asteroids.

Image above: The column of material at and just below the surface of dwarf planet Ceres (box) – the top layer contains anhydrous (dry) pyroxene dust accumulated from space mixed in with native hydrous (wet) dust, carbonates, and water ice. (Bottom) Cross section of Ceres showing the surface layers that are the subject of this study plus a watery mantle and a rocky-metallic core. Image Credits: Pierre Vernazza, LAM–CNRS/AMU.

“SOFIA, with its airborne location and sensitive FORCAST instrument, is the only observatory, currently operating or planned, that can make these kind of observations,” said Franck Marchis, planetary astronomer at the SETI Institute and one of Vernazza’s co-authors. “These and future mid-infrared observations are key to understanding the true nature and history of the asteroids.”

Ceres and asteroids are not the only context where material transported from elsewhere has affected the surfaces of solar system bodies. Dramatic examples include Saturn’s two-faced moon Iapetus and the red material seen by New Horizons on Pluto’s moon Charon. Planetary scientists also hypothesize that material from comets and asteroids provided a final veneer to the then-forming Earth that included substantial amounts of water plus the organic substances of the biosphere.

“Models of Ceres based on data collected by NASA’s Dawn spacecraft plus ground-based telescopes indicated substantial amounts of water- and carbon-bearing minerals such as clays and carbonates,” explains Vernazza. “Only the mid-infrared observations made using SOFIA were able to show that both silicate and carbonate materials are present on the surface of Ceres.”

To identify where the pyroxene on the surface of Ceres came from, Vernazza and his collaborators, including researchers from the SETI Institute in Mountain View, and NASA’s Jet Propulsion Laboratory, both in California, turned to interplanetary dust particles (IDPs) that form meteors when they are seen streaking through Earth’s atmosphere. The research team had previously shown that IDPs blasted into space by asteroid collisions are an important source of material accumulated on the surfaces of other asteroids. The implication is that a coating of IDPs has caused Ceres to take on the coloration of some of its dry and rocky neighbors.

NASA is exploring the solar system and beyond to better understand the universe and our place in it. We explore asteroids and comets, which may hold clues about the history of our solar system and how life arose on Earth.

SOFIA is a Boeing 747SP jetliner modified to carry a 100-inch diameter telescope. It is a joint project of NASA and the German Aerospace Center, DLR. NASA’s Ames Research Center in California’s Silicon Valley manages the SOFIA program, science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. The aircraft is based at NASA’s Armstrong Flight Research Center's Building 703, in Palmdale, California.

Where should NASA’s Juno spacecraft aim its camera during its next close pass of Jupiter on Feb. 2? You can now play a part in the decision. For the first time, members of the public can vote to participate in selecting all pictures to be taken of Jupiter during a Juno flyby. Voting begins Thursday, Jan. 19 at 11 a.m. PST (2 p.m. EST) and concludes on Jan. 23 at 9 a.m. PST (noon EST).

Image above: This amateur-processed image was taken on Dec. 11, 2016, at 9:27 a.m. PST (12:27 p.m. EST), as NASA’s Juno spacecraft performed its third close flyby of Jupiter. Image Credits: NASA/JPL-Caltech/SwRI/MSSS/Eric Jorgensen.

“We are looking forward to people visiting our website and becoming part of the JunoCam imaging team,” said Candy Hansen, Juno co-investigator from the Planetary Science Institute, Tucson, Arizona. “It’s up to the public to determine the best locations in Jupiter’s atmosphere for JunoCam to capture during this flyby.”

JunoCam will begin taking pictures as the spacecraft approaches Jupiter’s north pole. Two hours later, the imaging will conclude as the spacecraft completes its close flyby, departing from below the gas giant’s south pole. Juno is currently on its fourth orbit around Jupiter. It takes 53 days for Juno to complete one orbit.

“The pictures JunoCam can take depict a narrow swath of territory the spacecraft flies over, so the points of interest imaged can provide a great amount of detail,” said Hansen. “They play a vital role in helping the Juno science team establish what is going on in Jupiter’s atmosphere at any moment. We are looking forward to seeing what people from outside the science team think is important.”

There will be a new voting page for each upcoming flyby of the mission. On each of the pages, several points of interest will be highlighted that are known to come within the JunoCam field of view during the next close approach. Each participant will get a limited number of votes per orbit to devote to the points of interest he or she wants imaged. After the flyby is complete, the raw images will be posted to the JunoCam website, where the public can perform its own processing.

“It is great to be able to share excitement and science from the Juno mission with the public in this way,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “Amateur scientists, artists, students and whole classrooms are providing the world with their unique perspectives of Jupiter. I am really pleased that this website is having such a big impact and allowing so many people to join the Juno science team. The public involvement is really affecting how we look at the most massive planetary inhabitant in our solar system.”

During the Feb. 2 flyby, Juno will make its closest approach to Jupiter at 4:58 a.m. PST (7:58 a.m. EST), when the spacecraft is about 2,700 miles (4,300 kilometers) above the planet's swirling clouds.

JunoCam is a color, visible-light camera designed to capture remarkable pictures of Jupiter's poles and cloud tops. As Juno's eyes, it will provide a wide view of Jupiter over the course of the mission, helping to provide context for the spacecraft's other instruments. JunoCam was included on the spacecraft primarily for public engagement purposes, although its images also are helpful to the science team.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of Caltech in Pasadena, California.

This new, detailed global mosaic color map of Pluto is based on a series of three color filter images obtained by the Ralph/Multispectral Visual Imaging Camera aboard New Horizons during the NASA spacecraft’s close flyby of Pluto in July 2015. The mosaic shows how Pluto’s large-scale color patterns extend beyond the hemisphere facing New Horizons at closest approach, which were imaged at the highest resolution. North is up; Pluto’s equator roughly bisects the band of dark red terrains running across the lower third of the map. Pluto’s giant, informally named Sputnik Planitia glacier – the left half of Pluto’s signature “heart” feature – is at the center of this map. Note: Click on the image to view in the highest resolution. Image Credits: NASA/JHUAPL/SwRI.

A Colorful ‘Landing’ on Pluto

What would it be like to actually land on Pluto? This movie was made from more than 100 images taken by NASA’s New Horizons spacecraft over six weeks of approach and close flyby in the summer of 2015. The video offers a trip down onto the surface of Pluto -- starting with a distant view of Pluto and its largest moon, Charon -- and leading up to an eventual ride in for a "landing" on the shoreline of Pluto's informally named Sputnik Planitia.

A Colorful ‘Landing’ on Pluto

To create a movie that makes viewers feel as if they’re diving into Pluto, mission scientists had to interpolate some of the panchromatic (black and white) frames based on what they know Pluto looks like to make it as smooth and seamless as possible. Low-resolution color from the Ralph color camera aboard New Horizons was then draped over the frames to give the best available, actual color simulation of what it would look like to descend from high altitude to Pluto’s surface.

After a 9.5-year voyage covering more than three billion miles, New Horizons flew through the Pluto system on July 14, 2015, coming within 7,800 miles (12,500 kilometers) of Pluto. Carrying powerful telescopic cameras that could spot features smaller than a football field, New Horizons sent back hundreds of images of Pluto and its moons that show how dynamic and fascinating their surfaces are. Video Credits: NASA/JHUAPL/SwRI.

This stunning image, captured by the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys (ACS), shows part of the sky in the constellation of Sagittarius (The Archer). The region is rendered in exquisite detail — deep red and bright blue stars are scattered across the frame, set against a background of thousands of more distant stars and galaxies. Two features are particularly striking: the colors of the stars, and the dramatic crosses that burst from the centers of the brightest bodies.

While some of the colors in this frame have been enhanced and tweaked during the process of creating the image from the observational data, different stars do indeed glow in different colors. Stars differ in color according to their surface temperature: very hot stars are blue or white, while cooler stars are redder. They may be cooler because they are smaller, or because they are very old and have entered the red giant phase, when an old star expands and cools dramatically as its core collapses.

The crosses are nothing to do with the stars themselves, and, because Hubble orbits above Earth’s atmosphere, nor are they due to any kind of atmospheric disturbance. They are actually known as diffraction spikes, and are caused by the structure of the telescope itself.

Like all big modern telescopes, Hubble uses mirrors to capture light and form images. Its secondary mirror is supported by struts, called telescope spiders, arranged in a cross formation, and they diffract the incoming light. Diffraction is the slight bending of light as it passes near the edge of an object. Every cross in this image is due to a single set of struts within Hubble itself! Whilst the spikes are technically an inaccuracy, many astrophotographers choose to emphasize and celebrate them as a beautiful feature of their images.

The wavemaker moon, Daphnis, is featured in this view, taken as NASA's Cassini spacecraft made one of its ring-grazing passes over the outer edges of Saturn's rings on Jan. 16, 2017. This is the closest view of the small moon obtained yet.

Daphnis (5 miles or 8 kilometers across) orbits within the 42-kilometer (26-mile) wide Keeler Gap. Cassini's viewing angle causes the gap to appear narrower than it actually is, due to foreshortening.

The little moon's gravity raises waves in the edges of the gap in both the horizontal and vertical directions. Cassini was able to observe the vertical structures in 2009, around the time of Saturn's equinox (see PIA11654).

Like a couple of Saturn's other small ring moons, Atlas and Pan, Daphnis appears to have a narrow ridge around its equator and a fairly smooth mantle of material on its surface -- likely an accumulation of fine particles from the rings. A few craters are obvious at this resolution. An additional ridge can be seen further north that runs parallel to the equatorial band.

Fine details in the rings are also on display in this image. In particular, a grainy texture is seen in several wide lanes which hints at structures where particles are clumping together. In comparison to the otherwise sharp edges of the Keeler Gap, the wave peak in the gap edge at left has a softened appearance. This is possibly due to the movement of fine ring particles being spread out into the gap following Daphnis' last close approach to that edge on a previous orbit.

A faint, narrow tendril of ring material follows just behind Daphnis (to its left). This may have resulted from a moment when Daphnis drew a packet of material out of the ring, and now that packet is spreading itself out.

The image was taken in visible (green) light with the Cassini spacecraft narrow-angle camera. The view was acquired at a distance of approximately 17,000 miles (28,000 kilometers) from Daphnis and at a Sun-Daphnis-spacecraft, or phase, angle of 71 degrees. Image scale is 551 feet (168 meters) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

Roadside bedrock outcrops are all too familiar for many who have taken a long road trip through mountainous areas on Earth. Martian craters provide what tectonic mountain building and man's TNT cannot: crater-exposed bedrock outcrops.

Although crater and valley walls offer us roadside-like outcrops from just below the Martian surface, their geometry is not always conducive to orbital views. On the other hand, a crater central peak -- a collection of mountainous rocks that have been brought up from depth, but also rotated and jumbled during the cratering process -- produce some of the most spectacular views of bedrock from orbit.

This color composite cutout shows an example of such bedrock that may originate from as deep as 2 miles beneath the surface. The bedrock at this scale is does not appear to be layered or made up of grains, but has a massive appearance riddled with cross-cutting fractures, some of which have been filled by dark materials and rock fragments (impact melt and breccias) generated by the impact event. A close inspection of the image shows that these light-toned bedrock blocks are partially to fully covered by sand dunes and coated with impact melt bearing breccia flows.

mercredi 18 janvier 2017

In a paper published today in the journal Nature Communications, the BASE collaboration at CERN reports the most precise measurement ever made of the magnetic moment of the antiproton, allowing a fundamental comparison between matter and antimatter. The BASE measurement shows that the magnetic moments of the proton and antiproton are identical, apart from their opposite signs, within the experimental uncertainty of 0.8 parts per million. The result improves the precision of the previous best measurement by the ATRAP collaboration in 2013, also at CERN, by a factor of 6.

At the scale of elementary particles, an almost perfect symmetry between matter and antimatter exists. On cosmological scales, however, the amount of matter outweighs that of antimatter. Understanding this profound contradiction demands that physicists compare the fundamental properties of particles and their antiparticles with high precision.

BASE uses antiprotons from CERN’s unique antimatter factory, the Antiproton Decelerator (AD), and is designed specifically to perform precision measurements of the antimatter counterparts of normal matter particles. The magnetic moment, which determines how a particle behaves when immersed in a magnetic field, is one of the most studied intrinsic characteristics of a particle. Although different particles have different magnetic behaviour, the magnetic moments of protons and antiprotons are supposed to differ only in their sign as a consequence of so-called charge-parity-time symmetry. Any difference in their magnitudes would challenge the Standard Model of particle physics and would offer a glimpse of new physics.

Image above: The BASE collaboration at CERN reports the most precise measurement ever made of the magnetic moment of the antiproton, allowing a fundamental comparison between matter and antimatter (Image: Maximilien Brice/CERN).

To perform the experiments, the BASE collaboration cools down antiprotons to the extremely low temperature of about 1 degree above absolute zero, and traps them using sophisticated electromagnetic containers so that they do not come into contact with matter and annihilate (thanks to such devices, BASE has recently managed to store a bunch of antiprotons for more than one year). From here, antiprotons are fed one-by-one to further traps where their behaviour under magnetic fields allows researchers to determine their intrinsic magnetic moment. Similar techniques have already been successfully applied in the past to electrons and their antimatter partners, positrons, but antiprotons present a much bigger challenge because their magnetic moments are considerably weaker. The new BASE measurement required a specially designed magnetic “bottle” that is more than 1000 times stronger than that used in electron/positron experiments.

“This measurement is so far the culmination point of 10 years of hard work by the BASE team,” said Stefan Ulmer, spokesperson of the BASE collaboration. “Together with other AD experiments, we are really making rapid progress in our understanding of antimatter.”

BASE now plans to measure the antiproton magnetic moment using a new trapping technique that should enable a precision at the level of a few parts per billion – i.e. a factor of 200 to 800 improvement. “The implementation of this method is much more challenging than the method which was used here and will require several additional iteration steps,” says first author Hiroki Nagahama.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

NASA's Chandra X-ray Observatory has taken deep exposures of two nearby energetic pulsars flying through the Milky Way galaxy. The shape of their X-ray emission suggests there is a geometrical explanation for puzzling differences in behavior shown by some pulsars.

Pulsars − rapidly rotating, highly magnetized, neutron stars born in supernova explosions triggered by the collapse of massive stars − were discovered 50 years ago via their pulsed, highly regular, radio emission. Pulsars produce a lighthouse-like beam of radiation that astronomers detect as pulses as the pulsar's rotation sweeps the beam across the sky.

Since their discovery, thousands of pulsars have been discovered, many of which produce beams of radio waves and gamma rays. Some pulsars show only radio pulses and others show only gamma-ray pulses. Chandra observations have revealed steadier X-ray emission from extensive clouds of high-energy particles, called pulsar wind nebulas, associated with both types of pulsars. New Chandra data on pulsar wind nebulas may explain the presence or absence of radio and gamma-ray pulses.

This four-panel graphic shows the two pulsars observed by Chandra. Geminga is in the upper left and B0355+54 is in the upper right. In both of these images, Chandra’s X-rays, colored blue and purple, are combined with infrared data from NASA’s Spitzer Space Telescope that shows stars in the field of view. Below each data image, an artist’s illustration depicts more details of what astronomers think the structure of each pulsar wind nebula looks like.

For Geminga, a deep Chandra observation totaling nearly eight days over several years was analyzed to show sweeping, arced trails spanning half a light year and a narrow structure directly behind the pulsar. A five-day Chandra observation of the second pulsar, B0355+54, showed a cap of emission followed by a narrow double trail extending almost five light years.

The underlying pulsars are quite similar, both rotating about five times per second and both aged about half a million years. However, Geminga shows gamma-ray pulses with no bright radio emission, while B0355+54 is one of the brightest radio pulsars known yet not seen in gamma rays.

A likely interpretation of the Chandra images is that the long narrow trails to the side of Geminga and the double tail of B0355+54 represent narrow jets emanating from the pulsar’s spin poles. Both pulsars also contain a torus of emission spreading from the pulsar’s spin equator. These disk-shaped structures and the jets are crushed and swept back as the pulsars fly through the Galaxy at supersonic speeds

In the case of Geminga, the view of the torus is close to edge-on, while the jets point out to the sides. B0355+54 has a similar structure, but with the torus viewed nearly face-on and the jets pointing nearly directly towards and away from Earth. In B0355+54, the swept-back jets appear to lie almost on top of each other, giving a doubled tail.

Both pulsars have magnetic poles quite close to their spin poles, as is the case for the Earth’s magnetic field. These magnetic poles are the site of pulsar radio emission so astronomers expect the radio beams to point in a similar direction as the jets. By contrast the gamma-ray emission is mainly produced along the spin equator and so aligns with the torus.

For Geminga, astronomers view the bright gamma-ray pulses along the edge of the torus, but the radio beams near the jets point off to the sides and remain unseen. For B0355+54, a jet points almost along our line of sight towards the pulsar. This means astronomers see the bright radio pulses, while the torus and its associated gamma-ray emission are directed in a perpendicular direction to our line of sight, missing the Earth.

Chandra X-ray Observatory. Image Credits: NASA/CXC

These two deep Chandra images have, therefore, exposed the spin orientation of these pulsars, helping to explain the presence, and absence, of the radio and gamma-ray pulses.

The Chandra observations of Geminga and B0355+54 are part of a large campaign, led by Roger Romani of Stanford University, to study six pulsars that have been seen to emit gamma-rays. The survey sample covers a range of ages, spin-down properties and expected inclinations, making it a powerful test of pulsar emission models.

A paper on Geminga led by Bettina Posselt of Penn State University was accepted for publication in The Astrophysical Journal and is available online. A paper on B0355+54 led by Noel Klingler of the George Washington University was published in the December 20th, 2016 issue of The Astrophysical Journal and is available online. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.

New glitch for the "European GPS": several of the atomic clocks on board its satellites no longer work.

"This does not affect for the moment" the navigation system that has just started its services, according to the European Space Agency (ESA). "This is a sensitive issue", as atomic clocks are "very important" elements for the smooth operation of the satellite navigation system, which is a competitor to the US GPS, ESA Director General Jan Woerner said, A press conference in Paris.

Galileo satellites

However, in his view, we can not speak of "a new setback" for Galileo, which has experienced many delays and problems since the launch of the program in 1999. Its total cost is about ten billion euros .

So far 18 satellites have been launched. The constellation must count 30 operational satellites and two reserve ones by 2020. "The system is not questioned, not at all", Galileo "continues" but "we want to be transparent," said the official.

Four on each satellite

The atomic clocks of Galileo are supposed to ensure to the European system a very high precision. That is why each satellite carefully carries with it four atomic clocks of two types ("passive hydrogen masers" and rubidium atomic clocks). In order for each satellite to work well on this plane, at least one of the four clocks must be in good working order.

Passive hydrogen masers (atomic clock) by Argotec

Currently 9 out of 72 clocks are down (6 passive hydrogen masers, 3 rubidium atomic clocks), said Woerner, pointing out that "on every satellite there are at least two clocks that work."

"To date, thanks to this redundancy of clocks, none of the satellites in the constellation is out of order," he said.

Swiss Clocks

ESA is investigating the causes of the problem and has successfully restarted one of these clocks when previously it thought to have ten broken down. The satellites concerned have been launched at various times and the last ones, in orbit since November, are also concerned.

"We must learn the behavior of these atomic clocks and how to use them," Woerner said. They are manufactured by SpectraTime, based in Neuchâtel, with partners. SpectraTime confirmed to the ats that its experts are involved in research to identify the causes of the outage.

Rubidium atomic clock by SpectraTime

In this context, should the launch of four new Galileo satellites be delayed by an Ariane 5 rocket planned for the second half of 2017? "It's a sensitive issue," said Woerner. "If we wait and have other failures, we risk reducing the capacity of the system. But if we launch new satellites, they risk taking atomic clocks with problems. "

Do not delay the program

"Personally, I am in favor of not delaying the deployment of the constellation," he added. On 15 December, Europe launched the first services of its Galileo system, with the promise of a more precise location, reserved at present for the few possessors of compatible equipment.

Only a handful of privileged, possessors of the few smartphones compatible with Galileo (the first, the Aquaris X5 Plus of the Spanish manufacturer BQ, has been on the market since the autumn) can for now pick up the new signal.

These pioneers will be able to use the European system free of charge to find a pharmacy, the best route to go on holiday or settle their stride in the marathon. But for a mass arrival of products compatible with Galileo, we will have to be a little patient.

To the nearest centimeter

The European service aims to be more efficient with, in particular, a positioning of a precision, of the order of one meter, greater than that of its competitors. In addition, a paid service will allow a location within a few centimeters.

Galileo constellation

Moreover, the European signal will be dated to a few billionths of a second, a useful service for banks, insurance companies and energy suppliers.

Passive hydrogen masers must precisely ensure a stability of the nanosecond (one billionth of a second) per 24 hours, which is equivalent to losing or gaining a second every 2.7 million years. Rubidium clocks offer an accuracy of 10 nanoseconds per day.

As Galileo is compatible with GPS, the user can access both systems simultaneously and improve the quality and reliability of his position.

Earth’s 2016 surface temperatures were the warmest since modern recordkeeping began in 1880, according to independent analyses by NASA and the National Oceanic and Atmospheric Administration (NOAA).

Globally-averaged temperatures in 2016 were 1.78 degrees Fahrenheit (0.99 degrees Celsius) warmer than the mid-20th century mean. This makes 2016 the third year in a row to set a new record for global average surface temperatures.

The 2016 temperatures continue a long-term warming trend, according to analyses by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York. NOAA scientists concur with the finding that 2016 was the warmest year on record based on separate, independent analyses of the data.

Animated graphic above: The planet’s long-term warming trend is seen in this chart of every year’s annual temperature cycle from 1880 to the present, compared to the average temperature from 1880 to 2015. Record warm years are listed in the column on the right.Graphic Credits: NASA/Joshua Stevens, Earth Observatory.

Because weather station locations and measurement practices change over time, there are uncertainties in the interpretation of specific year-to-year global mean temperature differences. However, even taking this into account, NASA estimates 2016 was the warmest year with greater than 95 percent certainty.

“2016 is remarkably the third record year in a row in this series,” said GISS Director Gavin Schmidt. “We don’t expect record years every year, but the ongoing long-term warming trend is clear.”

The planet’s average surface temperature has risen about 2.0 degrees Fahrenheit (1.1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere.

Most of the warming occurred in the past 35 years, with 16 of the 17 warmest years on record occurring since 2001. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year – from January through September, with the exception of June – were the warmest on record for those respective months. October, November, and December of 2016 were the second warmest of those months on record – in all three cases, behind records set in 2015.

Phenomena such as El Niño or La Niña, which warm or cool the upper tropical Pacific Ocean and cause corresponding variations in global wind and weather patterns, contribute to short-term variations in global average temperature. A warming El Niño event was in effect for most of 2015 and the first third of 2016. Researchers estimate the direct impact of the natural El Niño warming in the tropical Pacific increased the annual global temperature anomaly for 2016 by 0.2 degrees Fahrenheit (0.12 degrees Celsius).

Weather dynamics often affect regional temperatures, so not every region on Earth experienced record average temperatures last year. For example, both NASA and NOAA found the 2016 annual mean temperature for the contiguous 48 United States was the second warmest on record. In contrast, the Arctic experienced its warmest year ever, consistent with record low sea ice found in that region for most of the year.

NASA’s analyses incorporate surface temperature measurements from 6,300 weather stations, ship- and buoy-based observations of sea surface temperatures, and temperature measurements from Antarctic research stations. These raw measurements are analyzed using an algorithm that considers the varied spacing of temperature stations around the globe and urban heating effects that could skew the conclusions. The result of these calculations is an estimate of the global average temperature difference from a baseline period of 1951 to 1980.

NOAA scientists used much of the same raw temperature data, but with a different baseline period, and different methods to analyze Earth’s polar regions and global temperatures.

GISS is a laboratory within the Earth Sciences Division of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The laboratory is affiliated with Columbia University’s Earth Institute and School of Engineering and Applied Science in New York.

NASA monitors Earth's vital signs from land, air and space with a fleet of satellites, as well as airborne and ground-based observation campaigns. The agency develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. NASA shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

mardi 17 janvier 2017

Scientists used NASA's Curiosity Mars rover in recent weeks to examine slabs of rock cross-hatched with shallow ridges that likely originated as cracks in drying mud.

"Mud cracks are the most likely scenario here," said Curiosity science team member Nathan Stein. He is a graduate student at Caltech in Pasadena, California, who led the investigation of a site called "Old Soaker," on lower Mount Sharp, Mars.

Image above: The network of cracks in this Martian rock slab called "Old Soaker" may have formed from the drying of a mud layer more than 3 billion years ago. The view spans about 3 feet (90 centimeters) left-to-right and combines three images taken by the MAHLI camera on the arm of NASA's Curiosity Mars rover. Image Credits: NASA/JPL-Caltech/MSSS.

If this interpretation holds up, these would be the first mud cracks -- technically called desiccation cracks -- confirmed by the Curiosity mission. They would be evidence that the ancient era when these sediments were deposited included some drying after wetter conditions. Curiosity has found evidence of ancient lakes in older, lower-lying rock layers and also in younger mudstone that is above Old Soaker.

"Even from a distance, we could see a pattern of four- and five-sided polygons that don't look like fractures we've seen previously with Curiosity," Stein said. "It looks like what you'd see beside the road where muddy ground has dried and cracked."

The cracked layer formed more than 3 billion years ago and was subsequently buried by other layers of sediment, all becoming stratified rock. Later, wind erosion stripped away the layers above Old Soaker. Material that had filled the cracks resisted erosion better than the mudstone around it, so the pattern from the cracking now appears as raised ridges.

Image above: This view of a Martian rock slab called "Old Soaker," which has a network of cracks that may have originated in drying mud, comes from the Mast Camera (Mastcam) on NASA's Curiosity Mars rover. It was taken on Dec. 20, 2016. The slab is about 4 feet long. Image Credits: NASA/JPL-Caltech/MSSS.

The team used Curiosity to examine the crack-filling material. Cracks that form at the surface, such as in drying mud, generally fill with windblown dust or sand. A different type of cracking with plentiful examples found by Curiosity occurs after sediments have hardened into rock. Pressure from accumulation of overlying sediments can cause underground fractures in the rock. These fractures generally have been filled by minerals delivered by groundwater circulating through the cracks, such as bright veins of calcium sulfate.

Both types of crack-filling material were found at Old Soaker. This may indicate multiple generations of fracturing: mud cracks first, with sediment accumulating in them, then a later episode of underground fracturing and vein forming.

"If these are indeed mud cracks, they fit well with the context of what we're seeing in the section of Mount Sharp Curiosity has been climbing for many months," said Curiosity Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory in Pasadena. "The ancient lakes varied in depth and extent over time, and sometimes disappeared. We're seeing more evidence of dry intervals between what had been mostly a record of long-lived lakes."

Besides the cracks that are likely due to drying, other types of evidence observed in the area include sandstone layers interspersed with the mudstone layers, and the presence of a layering pattern called cross-bedding. This pattern can form where water was flowing more vigorously near the shore of a lake, or from windblown sediment during a dry episode.

Image above: A grid of small polygons on the Martian rock surface near the right edge of this view may have originated as cracks in drying mud more than 3 billion years ago. Multiple Dec. 20, 2016, images from the Mastcam on NASA's Curiosity Mars rover were combined for this view of a rock called "Squid Cove." Image Credits: NASA/JPL-Caltech/MSSS.

Scientists are continuing to analyze data acquired at the possible mud cracks and also watching for similar-looking sites. They want to check for clues not evident at Old Soaker, such as the cross-sectional shape of the cracks.

The rover has departed that site, heading uphill toward a future rock-drilling location. Rover engineers at JPL are determining the best way to resume use of the rover's drill, which began experiencing intermittent problems last month with the mechanism that moves the drill up and down during drilling.

Curiosity landed near Mount Sharp in 2012. It reached the base of the mountain in 2014 after successfully finding evidence on the surrounding plains that ancient Martian lakes offered conditions that would have been favorable for microbes if Mars has ever hosted life. Rock layers forming the base of Mount Sharp accumulated as sediment within ancient lakes billions of years ago.

On Mount Sharp, Curiosity is investigating how and when the habitable ancient conditions known from the mission's earlier findings evolved into conditions drier and less favorable for life. For more information about Curiosity, visit: http://mars.jpl.nasa.gov/msl

This is the end of Swiss Space Systems or S3. The latter withdrew its appeal in respect of an application for bankruptcy.

The bankruptcy of Swiss Space System Holding Ltd. (S3) is final. The Payerne-based company (VD, Switzerland) withdrew its appeal, the Vaud Cantonal Court said on Tuesday.

Pascal Jaussi, CEO & Founder of S3

As a result of this withdrawal, the president of the Court of Prosecution and Bankruptcy indicated that the bankruptcy of S3 took effect on Monday 16th January at 16:15, specifies the press release of the Cantonal Court.

On December 14th, the District Court of the Broye and Northern Waldensians declared the bankruptcy of the aerospace company, which is the subject of numerous lawsuits exceeding 7 million francs. S3 wanted to launch minisatellites from a shuttle carried on the back of an airplane. The company also planned to organize weightless flights.

New tracking data confirms that NASA’s OSIRIS-REx spacecraft aced its first Deep Space Maneuver (DSM-1) on Dec. 28, 2016. The engine burn sets up the spacecraft for an Earth gravity assist this fall as it continues its two-year journey to the asteroid Bennu.

The large maneuver was the first using OSIRIS-REx’s main engines and resulted in a 964 miles per hour (431 meters per second) change in the vehicle’s velocity utilizing 780 pounds (354 kilograms) of fuel.

Deep Space Maneuver for NASA’s OSIRIS-REx Spacecraft

Tracking data from the Deep Space Network (DSN) confirmed the successful maneuver, and subsequent downlink of high-rate telemetry from the spacecraft shows that all subsystems performed as expected.

"DSM-1 was our first major trajectory change and first use of the main engines, so it’s good to have that under our belts and be on a safe trajectory to Bennu," said Arlin Bartels, deputy project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

DSM-1 represents the first major, post-launch milestone for OSIRIS-REx. The significant change in trajectory from DSM-1 was necessary to put OSIRIS-REx on course for an encounter with Earth in September of this year.

A smaller trajectory correction maneuver will be executed on Wednesday, Jan. 18 to refine the course for the Earth flyby, during which Earth's gravity will bend the OSIRIS-REx trajectory and slinging it toward a rendezvous with the asteroid Bennu in the fall of 2018.

NASA’s Goddard Space Flight Center provides overall mission management, systems engineering and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission’s observation planning and processing. Lockheed Martin Space Systems in Denver built the spacecraft and is providing spacecraft flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the agency’s New Frontiers Program for its Science Mission Directorate in Washington.

New images taken with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile have revealed otherwise invisible details of our Sun, including a new view of the dark, contorted centre of a sunspot that is nearly twice the diameter of the Earth. The images are the first ever made of the Sun with a facility where ESO is a partner. The results are an important expansion of the range of observations that can be used to probe the physics of our nearest star. The ALMA antennas had been carefully designed so they could image the Sun without being damaged by the intense heat of the focussed light.

Astronomers have harnessed ALMA's capabilities to image the millimetre-wavelength light emitted by the Sun’s chromosphere — the region that lies just above the photosphere, which forms the visible surface of the Sun. The solar campaign team, an international group of astronomers with members from Europe, North America and East Asia [1], produced the images as a demonstration of ALMA’s ability to study solar activity at longer wavelengths of light than are typically available to solar observatories on Earth.

ALMA observes a giant sunspot (3 millimetres)

Astronomers have studied the Sun and probed its dynamic surface and energetic atmosphere in many ways through the centuries. But, to achieve a fuller understanding, astronomers need to study it across the entire electromagnetic spectrum, including the millimetre and submillimetre portion that ALMA can observe.

Since the Sun is many billions of times brighter than the faint objects ALMA typically observes, the ALMA antennas were specially designed to allow them to image the Sun in exquisite detail using the technique of radio interferometry — and avoid damage from the intense heat of the focussed sunlight [2]. The result of this work is a series of images that demonstrate ALMA’s unique vision and ability to study our Sun.The data from the solar observing campaign are being released this week to the worldwide astronomical community for further study and analysis.

ALMA observes the full solar disc

The team observed an enormous sunspot at wavelengths of 1.25 millimetres and 3 millimetres using two of ALMA's receiver bands. The images reveal differences in temperature between parts of the Sun's chromosphere [3]. Understanding the heating and dynamics of the chromosphere are key areas of research that will be addressed in the future using ALMA.

Sunspots are transient features that occur in regions where the Sun's magnetic field is extremely concentrated and powerful. They are lower in temperature than the surrounding regions, which is why they appear relatively dark.

Image of the solar surface alongside a close-up view of a sunspot from ALMA

The difference in appearance between the two images is due to the different wavelengths of emitted light being observed. Observations at shorter wavelengths are able to probe deeper into the Sun, meaning the 1.25 millimetre images show a layer of the chromosphere that is deeper, and therefore closer to the photosphere, than those made at a wavelength of 3 millimetres.

Comparison of the solar disc in ultraviolet and millimetre wavelength light

ALMA is the first facility where ESO is a partner that allows astronomers to study the nearest star, our own Sun. All other existing and past ESO facilities need to be protected from the intense solar radiation to avoid damage. The new ALMA capabilities will expand the ESO community to include solar astronomers.

[2] Indeed, this lesson has been learned the hard way: the Swedish–ESO Submillimetre Telescope (SEST) had a fire in its secondary mirror assembly after the telescope was accidentally pointed at the Sun.

[3] A map of the whole disc of the Sun was also made with a single ALMA antenna, using a technique called fast-scanning, at a wavelength of 1.25 millimetres. The accuracy and speed of observing with a single ALMA antenna makes it possible to produce a map of the entire solar disc in just a few minutes. These maps show the distribution of temperatures in the chromosphere over the whole disc at low spatial resolution and therefore complement the detailed interferometric images of individual regions of interest.

More information:

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

lundi 16 janvier 2017

Euguene Cernan, the last man to walk on the moon, died Monday, Jan. 16, surrounded by his family.

Astronaut Eugene Cernan

Cernan, a Captain in the U.S. Navy, left his mark on the history of exploration by flying three times in space, twice to the moon. He also holds the distinction of being the second American to walk in space and the last human to leave his footprints on the lunar surface.

He was one of 14 astronauts selected by NASA in October 1963. He piloted the Gemini 9 mission with Commander Thomas P. Stafford on a three-day flight in June 1966. Cernan logged more than two hours outside the orbiting capsule.

In May 1969, he was the lunar module pilot of Apollo 10, the first comprehensive lunar-orbital qualification and verification test of the lunar lander. The mission confirmed the performance, stability, and reliability of the Apollo command, service and lunar modules. The mission included a descent to within eight nautical miles of the moon's surface.

"We leave as we came, and, God willing, we shall return, with peace and hope for all mankind." -- Cernan's closing words on leaving the moon at the end of Apollo 17.

In a 2007 interview for NASA's oral histories, Cernan said, "I keep telling Neil Armstrong that we painted that white line in the sky all the way to the Moon down to 47,000 feet so he wouldn't get lost, and all he had to do was land. Made it sort of easy for him."

Cernan concluded his historic space exploration career as commander of the last human mission to the moon in December 1972. En route to the moon, the crew captured an iconic photo of the home planet, with an entire hemisphere fully illumnitated -- a "whole Earth" view showing Africa, the Arabian peninsula and the south polar ice cap. The hugely popular photo was referred to by some as the "Blue Marble," a title in use for an ongoing series of NASA Earth imagery.

Cernan and crewmate Harrison H. (Jack) Schmitt completed three highly successful excursions to the nearby craters and the Taurus-Littrow mountains, making the moon their home for more than three days. As he left the lunar surface, Cernan said, "America's challenge of today has forged man's destiny of tomorrow. As we leave the moon and Taurus-Littrow, we leave as we came, and, God willing, we shall return, with peace and hope for all mankind."

"Apollo 17 built upon all of the other missions scientifically," said Cernan in 2008, recalling the mission as the agency celebrated its 50th Anniversary. "We had a lunar rover, we were able to cover more ground than most of the other missions. We stayed there a little bit longer. We went to a more challenging unique area in the mountains, to learn something about the history and the origin of the moon itself."

"I Was Strolling on the Moon One Day"

On their way to the moon, the Apollo 17 crew took one of the most iconic photographs in space-program history, the full view of the Earth dubbed "The Blue Marble." Despite it's fame, the photograph hasn't really been appreciated, Cernan said in 2007.

"What is the real meaning of seeing this picture? I've always said, I've said for a long time, I still believe it, it's going to be -- well it's almost fifty now, but fifty or a hundred years in the history of mankind before we look back and really understand the meaning of Apollo. Really understand what humankind had done when we left, when we truly left this planet, we're able to call another body in this universe our home. We did it way too early considering what we're doing now in space. It's almost as if JFK reached out into the twenty-first century where we are today, grabbed hold of a decade of time, slipped it neatly into the (nineteen) sixties and seventies (and) called it Apollo."

Image above: This classic photograph of the Earth was taken on December 7, 1972. Image Credit: NASA.

On July 1, 1976, Cernan retired from the Navy after 20 years and ended his NASA career. He went into private business and served as television commentator for early fights of the space shuttle.

ESA astronaut Thomas Pesquet completed his first spacewalk last Friday together with NASA astronaut Shane Kimbrough. The duo spent five hours and 58 minutes outside the International Space Station to complete a battery upgrade to the outpost’s power system.

The main task was to replace nickel-hydrogen batteries that store electricity from the Station’s solar panels with newer lithium-ion batteries that arrived recently aboard Japan’s cargo vessel.

Shane Kimbrough spacewalk

Thomas and Shane’s speed allowed them to perform a number of extra tasks once they had installed the batteries. They retrieved a failed camera, installed a protective cover on an unused docking port, moved handrails in preparation for future spacewalks and took pictures of external facilities for ground control to analyse.

Power upgrade

This spacewalk was the second in a week to upgrade the Station’s power supply. NASA astronaut Peggy Whitson and Shane spent six hours and 32 minutes outside installing adapter plates and connecting three of the six new batteries on 6 January.

Station solar panels and batteries

They practised this spacewalk for months on Earth at NASA’s Johnson Space Center, USA, and spent the last few weeks in space working intensively to prepare the spacesuits and tools for the sortie.

At NASA’s mission control in Houston, ESA astronaut Luca Parmitano directed the duo as lead communicator – a recognition of ESA’s expertise in Station operations.

Luca at Houston mission control

Luca is an experienced spacewalker himself, undertaking two sorties during his six-month mission in 2013. Luca guided the pair in space through their complex tasks, offering radio support and informing them of their extra tasks later in day.

Thomas commented on the spacewalk: “I have so much respect for all the teams who designed, built, launched the hardware and planned, tested, conceived, conducted the spacewalks... And all the teams who trained us so that we did not make too many mistakes! My hat off to everybody.”

Thomas spacewalker

With the time-consuming spacewalk over, the Station returns to normal operations, with many experiments using weightlessness to advance our knowledge.

Thomas is performing around 50 scientific experiments for ESA and France’s CNES space agency, as well as taking part in many more research activities for the other Station partners.